Icom IC-2820H User manual

S-14325XZ-C1
Mar. 2007
DUAL BAND FM TRANSCEVER
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This service manual describes the latest service information
for the IC-2820H DUAL BAND FM TRANSCEVER at the
time of publication.
NEVER connect the transceiver to an AC outlet or to a DC
power supply that uses more than 15 V. This will ruin the
transceiver.
DO NOT expose the transceiver to rain, snow or any liquids.
DO NOT reverse the polarities of the power supply when
connecting the transceiver.
DO NOT apply an RF signal of more than 20 dBm (100 mW)
to the antenna connector (J1). This could damage the
transceiver’s front end.
To upgrade quality, any electrical or mechanical parts and
internal circuits are subject to change without notice or
obligation.
MODEL VERSION
IC-2820H
USA-01
AUS-01
KOR-01
TPE-01
EXP-01
Be sure to include the following four points when ordering
replacement parts:
1. 10-digit order numbers
2. Component part number and name
3. Equipment model name and unit name
4. Quantity required
<SAMPLE ORDER>
1110003491 S.IC TA31136FNG IC-2820H MAIN UNIT 5 pieces
8820001210 Screw 2438 screw IC-2820H Top cover 10 pieces
Addresses are provided on the inside back cover for your
convenience.
Icom, Icom Inc. and logo are registered trademarks of Icom Incorporated (Japan) in the United States, the United
Kingdom, Germany, France, Spain, Russia and/or other countries.
ORDERING PARTS
1. Make sure a problem is internal before disassembling
the transceiver.
2. DO NOT open the transceiver until the transceiver is
disconnected from its power source.
3. DO NOT force any of the variable components. Turn
them slowly and smoothly.
4. DO NOT short any circuits or electronic parts. An
insulated tuning tool MUST be used for all adjustments.
5. DO NOT keep power ON for a long time when the
transceiver is defective.
6. DO NOT transmit power into a signal generator or a
sweep generator.
7. ALWAYS connect a 50 dB to 60 dB attenuator between
the transceiver and a Modulation Analyzer or spectrum
analyzer when using such test equipment.
8. READ the instructions of test equipment thoroughly
before connecting equipment to the transceiver.
REPAIR NOTES
INTRODUCTION CAUTION
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CONTENTS
SECTION 1 SPECIFICATIONS
SECTION 2 INSIDE VIEWS
SECTION 3 DISASSEMBLY INSTRUCTIONS
SECTION 4 CIRCUIT DESCRIPITON
4-1 RECEIVER CIRCUITS............................................................................................................... 4-1
4-2 TRANSMITTER CIRCUITS ....................................................................................................... 4-4
4-3 FREQUENCY SYNTHESIZER .................................................................................................. 4-6
4-4 POWER SUPPLY CIRCUITS..................................................................................................... 4-8
4-5 PORT ALLOCATIONS ............................................................................................................... 4-9
SECTION 5 ADJUSTMENT PROCEDURES
5-1 PREPARATION .......................................................................................................................... 5-1
5-2 FREQUENCY ADJUSTMENT ................................................................................................... 5-2
5-3 TRANSMIT ADJUSTMENT ....................................................................................................... 5-3
5-4 RECEIVE ADJUSTMENT .......................................................................................................... 5-4
SECTION 6 PARTS LIST
SECTION 7 MECHANICAL PARTS
SECTION 8 BOARD LAYOUTS
SECTION 9 BLOCK DIAGRAM
SECTION 10 VOLTAGE DIAGRAM
SECTION 11 HM-133
SECTION 12 UT-123 (Optional product)
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1 - 1
SECTION 1 SPECIFICATIONS
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3 - 1
SECTION 3 DISASSEMBLY INSTRUCTION
1. Removing the top cover
qUnscrew 10 screws, then remove the top cover.
3. Removing the MAIN UNIT
qUnscrew 11 screws from the MAIN UNIT.
2. Removing the bottom cover
qUnscrew 7 screws, then remove the bottom cover.
10 screws
Top cover
wDisconnect the speaker cable.
Speaker cable
Bottom cover
7 screws
wDisconnect the cooling fan cable, and unsolder 6 points at
the antenna connectors (grey colored).
6 unsoldering points
Cooling fan cable
MAIN UNIT
eRemove the MAIN UNIT in the direction of the arrow.
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12 - 2
• MAIN UNIT (BOTTOM VIEW)
05C
15C
C52
C53
C54
C100
C101
C205
C206
C207
C208
902C
C210
C212
C352
C353
C354
653C
753C
853C
C360
C361
C362
C363
463C
073C
173C
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553PE
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202CI
IC350
IC352
353CI
Q50
15Q
812Q
Q219
422Q
05R
R203
R204
R205
R206
R208
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012R
503R
R353
453R
553R
563R
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2J
0H 5H 01H51H02H52H03H53H04H 54H05H55H 06H
V0V5V10V15V20V25V30V35V40V45V50V55V60
• MAIN UNIT (TOP VIEW)
1C
2C
C
201C
301C
C104
C106
C107
C108
C109
011C
C111
C112
311C
411C
C116
C117
C200
C201
C202
302C
C204
C211
312C
C214
612C
003C
C301
20C
C303
C304
013C
C350
C351
55C
C366
C367
863C
C369
273C
473C
C375
C376
773C
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001PE
002PE
102PE
P202
302PE
EP300
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EP352
EP353
IC1
IC102
102CI
302CI
IC300
103CI
453CI
IC357
953CI
063CI
163CI
J1
Q1
2Q
001Q
002Q
Q201
Q202
Q221 Q222
322Q
R1
R2 R3
R100
401R
501R
R106 R107
R108
901R
202R 702R
112R
212R
R213
412R
512R
R216
71R
R300
R301
20R
303R
403R
603R
R307
013R
R350
153R
25R
R357
R362
R363
R367
R373
873R
R383
R385
R386
783R
R390
193R
R392
393R
493R
69R
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002X
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KC
DT
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0H5H
01H51H
02H52H03H5
3H04H54H05H55H06H
V0 V5 V10 V15 V20 V25 V30 V35 V40 V45 V50 V55 V60
• BOARD LAYOUTS
 
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1-1-32, Kamiminami, Hirano-ku, Osaka 547-0003, Japan S-14310XZ-C1
© 2007 Icom Inc.
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